package ycl.gateway.config;

import org.springframework.beans.factory.ObjectProvider;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.web.ResourceProperties;
import org.springframework.boot.autoconfigure.web.ServerProperties;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.boot.web.reactive.error.ErrorAttributes;
import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.codec.ServerCodecConfigurer;
import org.springframework.web.reactive.result.view.ViewResolver;
import ycl.gateway.exception.ExceptionHandler;

import java.util.Collections;
import java.util.List;

/**
 * 统一异常处理器
 *
 * @author ycl
 * @date 2022/9/23 0023 13:42:47
 */
@Configuration
@EnableConfigurationProperties({ServerProperties.class, ResourceProperties.class})
public class ExceptionConfig {

	private final ServerProperties serverProperties;
	private final ApplicationContext applicationContext;
	private final ResourceProperties resourceProperties;
	private final List<ViewResolver> viewResolvers;
	private final ServerCodecConfigurer serverCodecConfigurer;

	public ExceptionConfig(
			ServerProperties serverProperties,
			ResourceProperties resourceProperties,
			ObjectProvider<List<ViewResolver>> viewResolversProvider,
			@Autowired(required = false)
			ServerCodecConfigurer serverCodecConfigurer,
			ApplicationContext applicationContext) {
		this.serverProperties = serverProperties;
		this.applicationContext = applicationContext;
		this.resourceProperties = resourceProperties;
		this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
		this.serverCodecConfigurer = serverCodecConfigurer;
	}

	@Bean
	@Order(Ordered.HIGHEST_PRECEDENCE)
	public ErrorWebExceptionHandler errorWebExceptionHandler(
			@Autowired(required = false)
			ErrorAttributes errorAttributes) {
		ExceptionHandler exceptionHandler = new ExceptionHandler(errorAttributes,
				this.resourceProperties, this.serverProperties.getError(), this.applicationContext);
		exceptionHandler.setViewResolvers(this.viewResolvers);
		exceptionHandler.setMessageWriters(this.serverCodecConfigurer.getWriters());
		exceptionHandler.setMessageReaders(this.serverCodecConfigurer.getReaders());
		return exceptionHandler;
	}
}
